Astronomers and Star Gazers need a challenge when observing. Novices can be easily overwhelmed by long lists of challenging objects. Expert observers can be so focused on their projects, they easily can ignore the challenge provided by observing with different instruments.
By presenting three objects in each of several different groups, the hope is to provide all observers, no matter what their experience level, no matter what type of instruments they have access to, challenging objects to observe. There is even a group for the one instrument we are all born with, the naked-eye. Astrophotographers and astroimagers are not ignored here, either.
No matter what your experience, no matter what you use to observe, get outside and “Keep looking up!”
April’s Sky Challenges
- M6, an open cluster of about 80 stars in Scorpius. It is also called the Butterfly Cluster and is about 25′ across.
- M7, an open cluster in Scorpius. Also called the Ptolemy Cluster, it contains about 80 stars in an area about 80′ across.
- M44, a third magnitude open cluster of about 1000 stars in Cancer. This large (95′ ) open cluster is known as the Beehive or Praesepe.
- Regulus, or α Leonis, is the brightest star in the constellation Leo and one of the brightest stars in the nighttime sky. It is a multiple star system composed of four stars which are separated into two pairs. The spectroscopic binary Regulus A consists of a blue-white main sequence star and its companion which has not yet been directly observed, but is probably a white dwarf star. Located 177″ away is the pair Regulus B and Regulus C, which are dim main-sequence stars.Regulus A is a class B7 V main sequence star. Regulus B is a dwarf type K1-2 V star and Regulus C is a red dwarf M5 V class star.
- ο Leonis, which carries the ancient name of Subra, is a optical and spectroscopic mulitple star system with an oddball primary star. ο Leonis A is a spectroscopic binary comprised of a type F6m star with an A5m secondary with a separation of 0.165 AU, or about half the orbital distance of Mercury. Both stars show an abundance of heavy elements and deficiencies of calcium and scandium, and are listed as “metallic line” stars. The optical companion, ο Leonis C, lies 1.5′ to the northeast of ο Leonis A. It is an 11th mgnitude yellow star.
- The Coma Star Cluster in Coma Berenices, also called Melotte 111, is a small but nearby star cluster in our galaxy, containing about 40 stars, from magnitude 5 to 10, with a common proper motion. The open cluster has a distance of 288 light-years, roughly twice as distant as the Hyades, and covers an area of more than 5 degrees on the sky.
Small Telescope Challenges
- For 2″ to 6″ telescopes:
- 54 Leonis is a beautiful binary pair with a separation of 6.5″. At magnitudes 4.5 and 6.3 this is a great double for the medium to small scope. The primary star is white of spectral type A1 V and the companion is a blue, class A2 Vn star.
- NGC 3521 is a tenth magnitude intermediate type SABbc spiral galaxy in Leo.
- Messier 66, also known as NGC 3627, is an intermediate spiral galaxy of type SAB(s)b in Leo. M66 is about 95,000 light-years across, with pronounced dust lanes and bright star clusters along sweeping spiral arms. M66 is part of the Leo Triplet, a small group of galaxies that also includes M65 and NGC 3628, that is popular with astrophotographers.
Medium Telescope Challenges
- For 8″ to 14″ telescopes:
- γ Leonis is a binary star system, with the traditional name Algieba. The brighter component has an apparent magnitude of +2.28 and is of spectral class K1-III bCN-0.5. The companion star has an apparent magnitude of +3.51 and belongs to the spectral class G7 IIICN-I. Both stars are giants and the separation is 4″ or about 170 AU.
- NGC3377 is a 10th magnitude elliptical galaxy in Leo, and it appears as a well-defined oval, instead of a near-circle or a thin cigar-shape. It is a member of a group of more than a dozen galaxies called the Leo I Group .
- M105 is a type E1 elliptical galaxy and at tenth magnitude it is tthe brightest member of the Leo I galaxy grouping, which includes M95 and M96. M105 also has a dust lane just above the core reminiscent of NGC5128.
Large Telescope Challenges
- For 16″ and larger telescopes:
- NGC3395 and NGC3396 is an interesting pair of interacting galaxies. NGC3396 is larger of the two with a size of 3.4’ X 1.3’ and has a magnitude of 12.1. NGC3395 is the same magnitude but is smaller with a size of 1.6’ X 0.9’. They are both elongated and together they look like a butterfly. NGC3395 is more concentrated and has a soft nucleus. NGC 3396 has a brighter stellar core. This pair is also known as Arp 270.
- The 11th magnitude lenticular galaxy NGC3412 in Leo
- WOLF 359 is fascinating, not only for being the location of a fictional grand battle against the Borg, but because it is the third closest star to our own solar system at 7.75 light years. With a magnitude of 13.5 and its large apparent motion, it is always a challenge to find this dim red type M6.5 Ve dwarf.
- Novice: Star Trails
- Intermediate: M13
- Expert: Gamma Group of galaxies in Leo
Extra Credit Challenge
The Jackalope is one of the rarest animals in the world and are extremely shy, unless approached.
As gentle as these creatures may seem, they are in truth, killer rabbits. And as such are very aggressive and unpredictable, and should not be provoked for any reason.
It has also been said that the jackalope can convincingly imitate any sound, including the human voice. It uses this ability to elude pursuers, chiefly by using phrases such as “There he goes! That way!” During days of the Old West, when cowboys gathered by the campfires singing at night, jackalopes could often be heard mimicking their voices.
It is said that a jackalope may be caught by putting a flask of whiskey out at night. The jackalope will drink its fill of whiskey and its intoxication will make it easier to hunt. It has also been said that jackalopes will only breed during electrical storms including hail, explaining its rarity.